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41.
Júlia Domján Annamária Fricska Lajos Madarász Martin Gyürkés Ákos Köte Attila Farkas Panna Vass Csaba Fehér Balázs Horváth Kálmán Könczöl Hajnalka Pataki Zsombor Kristóf Nagy György János Marosi Edit Hirsch 《Biotechnology progress》2020,36(6):e3052
The use of Process Analytical Technology tools coupled with chemometrics has been shown great potential for better understanding and control of mammalian cell cultivations through real-time process monitoring. In-line Raman spectroscopy was utilized to determine the glucose concentration of the complex bioreactor culture medium ensuring real-time information for our process control system. This work demonstrates a simple and fast method to achieve a robust partial least squares calibration model under laboratory conditions in an early phase of the development utilizing shake flask and bioreactor cultures. Two types of dynamic feeding strategies were accomplished where the multi-component feed medium additions were controlled manually and automatically based on the Raman monitored glucose concentration. The impact of these dynamic feedings was also investigated and compared to the traditional bolus feeding strategy on cellular metabolism, cell growth, productivity, and binding activity of the antibody product. Both manual and automated dynamic feeding strategies were successfully applied to maintain the glucose concentration within a narrower and lower concentration range. Thus, besides glucose, the glutamate was also limited at low level leading to reduced production of inhibitory metabolites, such as lactate and ammonia. Consequently, these feeding control strategies enabled to provide beneficial cultivation environment for the cells. In both experiments, higher cell growth and prolonged viable cell cultivation were achieved which in turn led to increased antibody product concentration compared to the reference bolus feeding cultivation. 相似文献
42.
Sorghum [Sorghum bicolor (L.) Moench] can benefit from accelerated breeding and release of improved varieties through doubled haploid technology. The technology has been used in speeding up the breeding of other major cereals such as wheat, maize and rice, for which generally widely applied optimised protocols exist. A reproducible protocol for the crop, that can overcome genotype dependency and other species-specific challenges such as phenolic exudation is however lacking. This study aimed at sorghum doubled haploids production thereby contributing to the development of an improved protocol. From the 28 hybrid genotypes, both F1 registered- and experimental hybrids involved, this study successfully produced haploids from five genotypes and subsequently, four confirmed doubled-haploid lines on W14mf medium or its modification with 1.0 gl−1 L-proline, 1.0 gl−1 L-asparagine and 1.0 gl−1 KH2PO4. Medium 190-2Cu was used for regeneration and rooting, which occurred successfully, if the calli were transferred on to it less than 7 days after induction, and temperature was maintained at 25˚C under light condition. Genotype dependency was not wholly overcome; however, sorghum’s high tillering ability and abiotic stress tolerance were observed to contribute to attainment of haploid plantlets. Spontaneous diploids producing seeds at rates of upto 80.5% were obtained, therefore eliminating the need for colchicine duplication. 相似文献
43.
Birthe Tegtmeyer Gabrielle Vieyres Daniel Todt Chris Lauber Corinne Ginkel Michael Engelmann Maike Herrmann Christian K. Pfaller Florian W. R. Vondran Ruth Broering Ehsan Vafadarnejad Antoine-Emmanuel Saliba Christina Puff Wolfgang Baumgrtner Csaba Miskey Zoltn Ivics Eike Steinmann Thomas Pietschmann Richard J. P. Brown 《Journal of virology》2021,95(10)
44.
45.
Tibor Németh Adél Tóth Judit Szenzenstein Péter Horváth Joshua D. Nosanchuk Zsuzsanna Grózer Renáta Tóth Csaba Papp Zsuzsanna Hamari Csaba Vágv?lgyi Attila Gácser 《PloS one》2013,8(7)
The C. parapsilosis sensu lato group involves three closely related species, C. parapsilosis sensu stricto,
C
. orthopsilosis
and
C
. metapsilosis
. Although their overall clinical importance is dramatically increasing, there are few studies regarding the virulence properties of the species of the psilosis complex. In this study, we tested 63 C. parapsilosis sensu stricto, 12
C
. metapsilosis
and 18
C
. orthopsilosis
isolates for the ability to produce extracellular proteases, secrete lipases and form pseudohyphae. Significant differences were noted between species, with the
C
. metapsilosis
strains failing to secrete lipase or to produce pseudohyphae. Nine different clinical isolates each of C. parapsilosis sensu stricto,
C
. orthopsilosis
and
C
. metapsilosis
were co-cultured with immortalized murine or primary human macrophages. C. parapsilosis sensu stricto isolates showed a significantly higher resistance to killing by primary human macrophages compared to
C
. orthopsilosis
and
C
. metapsilosis
isolates. In contrast, the killing of isolates by J774.2 mouse macrophages did not differ significantly between species. However, C. parapsilosis sensu stricto isolates induced the most damage to murine and human macrophages, and
C
. metapsilosis
strains were the least toxic. Furthermore, strains that produced lipase or pseudohyphae were most resistant to macrophage-mediated killing and produced the most cellular damage. Finally, we used 9 isolates of each of the C. parapsilosis sensus lato species to examine their impact on the survival of
Galleria
mellonella
larvae. The mortality rate of
G
. mellonella
larvae infected with
C
. metapsilosis
isolates was significantly lower than those infected with C. parapsilosis sensu stricto or
C
. orthopsilosis
strains. Taken together, our findings demonstrate that
C
. metapsilosis
is indeed the least virulent member of the psilosis group, and also highlight the importance of pseudohyphae and secreted lipases during fungal-host interactions. 相似文献
46.
Many attempts on optimization of sorghum [Sorghum bicolor (L.)
Moench] tissue culture induction media have been made, but the culture system
remains with some bottlenecks compared to that of other crops. This study aimed
at assessing the suitability of various induction media to produce embryogenic
callus (yellow and friable) with high induction rates and reduced phenolic
exudation. The six culture medium modifications: 3 based on Murashige and
Skoog (MS) medium and one each based on Chu N6, Gamborg B5 and 190-2
media respectively were applied in the culture of mature embryos from 10
sorghum genotypes. Although there was a genotype influence on the attainment
of a yellow callus, friability of the callus was determined to be dependent on the
culture medium and not the genotype. Half strength MS medium with 0.2 mg/l
2,4-D with 2.8 g/l Gelrite® as the gelling agent modified with 1.0 g/l KH2PO4,
1.0 g/l L-proline, 1.0 g/l L-asparagine and 0.16 mg/l CuSO4·5H2O (type E) was
found to be the most effective resulting in about 60% yellow coloured callus
induction with 25% friability. Addition of CuSO4·5H2O, KH2PO4, L-proline and
L-asparagine significantly reduced the phenolic production. Half strength MS
medium was observed to contribute to quality callus production when compared
to full strength MS media modified with the compounds. The half strength MS
medium was also observed to suppress phenolic production. Medium 190-2
produced the highest regeneration frequency (40%) among the 3-regeneration
media tested. The results provide information on a suitable sorghum callus
induction medium necessary for embryogenesis. 相似文献
47.
Balázs Csaba Németh Thomas Wartmann Walter Halangk Miklós Sahin-Tóth 《The Journal of biological chemistry》2013,288(33):24049-24062
Chymotrypsin C (CTRC) is a proteolytic regulator of trypsinogen autoactivation in humans. CTRC cleavage of the trypsinogen activation peptide stimulates autoactivation, whereas cleavage of the calcium binding loop promotes trypsinogen degradation. Trypsinogen mutations that alter these regulatory cleavages lead to increased intrapancreatic trypsinogen activation and cause hereditary pancreatitis. The aim of this study was to characterize the regulation of autoactivation of mouse trypsinogens by mouse Ctrc. We found that the mouse pancreas expresses four trypsinogen isoforms to high levels, T7, T8, T9, and T20. Only the T7 activation peptide was cleaved by mouse Ctrc, causing negligible stimulation of autoactivation. Surprisingly, mouse Ctrc poorly cleaved the calcium binding loop in all mouse trypsinogens. In contrast, mouse Ctrc readily cleaved the Phe-150–Gly-151 peptide bond in the autolysis loop of T8 and T9 and inhibited autoactivation. Mouse chymotrypsin B also cleaved the same peptide bond but was 7-fold slower. T7 was less sensitive to chymotryptic regulation, which involved slow cleavage of the Leu-149–Ser-150 peptide bond in the autolysis loop. Modeling indicated steric proximity of the autolysis loop and the activation peptide in trypsinogen, suggesting the cleaved autolysis loop may directly interfere with activation. We conclude that autoactivation of mouse trypsinogens is under the control of mouse Ctrc with some notable differences from the human situation. Thus, cleavage of the trypsinogen activation peptide or the calcium binding loop by Ctrc is unimportant. Instead, inhibition of autoactivation via cleavage of the autolysis loop is the dominant mechanism that can mitigate intrapancreatic trypsinogen activation. 相似文献
48.
49.
50.
Maurizio G. Paoletti Robert J. Blakemore Csaba Csuzdi Luca Dorigo Angelo Leandro Dreon Federico Gavinelli Francesca Lazzarini Nicola Manno Enzo Moretto David Porco Enrico Ruzzier Vladimiro Toniello Andrea Squartini Giuseppe Concheri Marina Zanardo Javier Alba-Tercedor 《PloS one》2016,11(3)
A new Italian earthworm morphologically close to the similarly large and anecic Eophila tellinii (Rosa, 1888) is described. Distribution of Eophila crodabepis sp. nov. extends over 750 km2 from East to West on the Asiago Plateau and Vittorio Veneto Hills, from North to South on mounts Belluno Prealps (Praderadego and Cesen), Asiago, Grappa and onto the Montello foothills. This range abuts that of Eophila tellinii in northern Friuli Venezia Giulia region. Known localities of both E. tellinii and E.crodabepis sp. nov. are mapped. mtDNA barcoding definitively separates the new western species from classical Eophila tellinii (Rosa, 1888). 相似文献